Mumbai: A day after stock market benchmark Nifty witnessed a 900-point flash crash, Finance Minister P Chidambaram on Saturday said the matter is being investigated and regulator Sebi would take necessary actions in this regard.

Addressing the media after meeting Sebi top officials here, he said that he has been told that there was no systemic risk in the capital market and the stock exchange NSE had come out with a statement explaining the incident.

He said the NSE had said it is investigating the matter and market regulator Sebi (Securities and Exchange Board of India) would take necessary actions.

He was replying to queries on fall of about 900 points or close to 16 percent in Nifty within seconds in a flash crash like situation yesterday morning, which led to a halt in trading at NSE for about 15 minutes.

"I was assured there was no systemic risk," he said.

Asked further about the issue, the minister on a lighter note said he did not understand the technical issues like 'algo trade and non-algo trade' and read out the statement issued by NSE yesterday.

The NSE had said there was no technical glitch in its system and blamed the crash on erroneous orders worth over Rs 650 crore for multiple trades by broker Emkay Global in various stocks at low prices on behalf of an "institutional client".

While NSE said it is investigating into the incident, sources have said market watchdog Sebi had also begun a probe yesterday itself into the 'flash crash'.

Sebi is looking into all aspects of the incident, including the probability of technical problems or any intentional manipulative activities by some vested interests, as per a senior regulatory official.

The incident occurred on a day when expectations were high for an upward rally on bourses, following some big-ticket reform measures approved by the government on Thursday, including on FDI in sectors like insurance and pension.

Sebi is looking into the entire trading pattern of broker concerned Emkay Global, which has been disabled by NSE from trading, as also the trade details of the affected stocks.

Sebi would look into whether adequate safeguard mechanism was in place to avoid a 'flash crash' like situation, as the so-called freak trades were executed in a number of well-known blue chip stocks, including some large banking shares.

While there is no circuit filter in large blue-chip stocks, market systems are supposed to be well-prepared to handle any mischief or large erroneous trades.

The regulator is also concerned that instances of 'freak trades' seem to be on the rise.

NSE has said the abnormal orders were 'non-algo' in nature and were entered for an erroneous quantity which resulted in executing trades at multiple price points across the entire order book. The exchange has also identified these orders to a specific dealer terminal.

Sebi is already looking into issues related to algorithmic trade -- a latest-technology mechanism that allows execution of orders at a very high speed to take benefit of smallest of the change in share price.

This trade mechanism has been criticised in various quarters on apprehensions that it helps market manipulators to take benefit of the high-speed technology.

Sebi has been looking at ways to avoid 'flash crash' like situations in Indian markets for quite some time.